Alter
by Ao No Demon Boy
Summary: When the Vatican kidnaps Rin and turns him into a mindless killing machine, Yukio and the others must team together and save the altered demon from a fate some deem worse than death. (Ratings will change as the story is updated)
1. Chapter 1

Silence enveloped the torch and chandelier lit chamber, a hush covering the mouths of many as one young blonde spoke, voice bold and shouting out to the listeners of the roon. The Grigori remained silent as the blonde male stood before them, voice loud and reverberating off of the aging marble walls, "He must be contained and trained!" The tall male bellowed, one hand absently resting on the hilt of his sword. The paladin waited for the answer from the hidden faces of the Grigori members.

"And then what do you suppose we do Paladin Auguste?" A female voice returned.

The room was silent once more as Arthur gathered his response, a cold tingle tremoring up his spine as he could not believe the next few words would leave his mouth. "We do as Mr Pheles proposed, raise the boy as a weapon to dispose of any threats to us. What could be stronger than the son of Satan?"

The room was an uproar or whispers, until one commanding voice silenced them all, "And how do we know that the boy will do as we ask?"

Arthur Angel Aguste could not help but laugh quite audibly, his laugh echoing of the walls around then, "My good sir, when have we ever asked the permission of a demon?" He asked rhetorically, head still arched and gazing up the at beings before him.

The room once more was taken over by parties of whispers, worries and small cries erupting from some as they called out, "He'll kill us all" and "He's mad!". Though these cries were silenced once more. "Silence! You have convinced us Sir Aguste. You have our permission. Though... to capture such a beast you may need the power of a beast. We command that you gain Sir Pheles' help."

More whispers erupted and suddenly a shrouded figure emerged from the shadows of the surrounding walls, a smirk playing upon pale lips, as hands toyed with violet hair. "I would be honoured to help the Paladin gain capture over the young Okumura child." Mephisto said with that same smirk plastered on his flesh. _'This will be entertaining'_ the demon thought to himself, eyes quickly shifting down to the quivering form in his coat pocket, a small green head poking itself out to study the outside, but not enough to gain the attention of the humans inhabiting the room. _'Very fun indeed'._

"Shall we?" The green eyed demon inquired tapping his umbrella on the stone floor thrice, "Eins, zwei, drie!"


	2. Chapter 2

_BEEP BEEP BEEP_

7:00 am

Rin Okumura was snoring as loudly as usual, soft rumbles vibrating in his chest as he lay on his belly, tail swaying lazily in the air as he dreamed, ears falling deaf upon the screeching beeping on the digital alarm clock on the desk only a few metres away. What did wake his though was a rush shove to his shoulder and the loud voice of his slightly younger twin.

Having already woke up to his separate alarm at around 6:45, Yukio Okumura was already dressed and preparing for the day when the alarm he had set for Rin sounded, he cursed lowly at the loudness of it, hoping that it might actually work this time. Alas, it didn't. Instead of the intended normal reaction of waking up, Rin only snored louder, which made Yukio more annoyed, he was baffled by the fact that he was actually more mature then the eldest of the two.

Sighing heaver than normal when dealing with Rin, Yukio shoved the other hard on the shoulder, being careful not to bump the tail in memory of the last time, it didn't really sit well. "Rin, get up, or you'll be late..." He sighed before increasing his volume "Again!" He was used to Rin not listening to him at this early, or any time of the day for that matter, it was an everyday occurrence.

"Get up or... I'll never let you have Sukiyaki ever again!" He yelled with an evil smirk, this was bound to work when all else failed. Rin would never let that stand and surely this had to wake him up.

In less than what seemed as no time at all the demons eyes shot open and sat up with gusto. Eyes shooting daggers at his twin as his tail became bushier than normal. A sign that the teen was not impressed.

"Don't you dare" The teen growled, fangs showing ever slow slightly in a look that would scare any average human, but not his brother, Yukio was smarter than, knowing that the other was always this grumpy in the morning, his usual cheerier demeanour appearing after he could have shoved some sugar of caffeine into the shorter males system.

With a loud yawn Rin stretch backwards onto the bed, arching his back as a soft mewl left his mouth. A few months after the whole gate debacle Rin and his more demonic side had begun making feline sounding noises every so often whether it be a mewl, mroew or a hiss. Yukio found it quite amusing and used it as blackmail against his twin at any point he could. Rin did not like this at all.

Stifling a chuckle, Yukio shook his head "Stop meowing and start getting ready or else I will ban you from it, breakfast is on my bed, I have to go and plan for my next class, so unless you don't want me leaking audio recordings of you acting like Kuro, I suggest you don't be late" He smiled, it was unnerving indeed and worked on Rin nine times out of ten.

Eyes wide once more with a tingle of fright Rin let out a frightened cat like screech. "You're evil bro" the dark haired male replied.

Shaking his head once more, Yukio chuckled and made his way out the door and off to prepare.

_"Is he gone? He's scary!"_ came a little voice from under the blankets, Kuro, Rin's familiar, was underneath the warm blankets, curled up to Rin as normal on a cold night. _"He smiles when he is angry"_ He hid himself under Rin's pyjama shirt _"Scaaarryyy!"_

Looking down as his furry familiar, he placed a hand on the two tailed feline and patted his fur gently. "I know bud, I know" The demon said petting the sidth's fur and withdrawing the cat demon from inside his shirt, "Watch your claws there Kuro" Placing the cat back on the bed he covered the creature with his blanket before standing and looking over at the meal that was sitting on the bed, "Ok, let's hope that Ukobach made this and not Yukio." Rin said and playfully doing the Hail Mary gesture before hissing afterwards as it stung his flesh, "Really gotta remember I'm like... a demon and shit" Rin continued before shrugging it off and making his way to the food and in no time at all devouring it all with absolutely no manners or any sort, leaving a small portion for Kuro to eat when he was hungry.

"Ok... have to get ready" He said as his gaze slowly moved over to the warm bed of which he had just left. "Maybe ten more minutes wouldn't hurt."

**/*_*\**

Yukio stood before the class, eyes downcast as he marked the attendance of the small class, a shiver of anger trickling up his spine as his 'older' brother had yet to turn up to class yet.

"Suguro?" Yukio called out awaiting a response from the duel haired male.

"Here teach" was all that was said.

As the room was silent, panting could be heard as well as the fast paced clicks of running feet before the door unceremoniously slammed open and on the other side was a breathless Rin, cheeks flushed red and mouth agape with heavy pants, "Sorry..." He panted out, "Slept... in..."

Looking at his twin all Rin could do was gulp as he stared at the furious eyes of his brother, "I'll sit down now" The dark haired boy said as he ran to his seat beside Shiemi and dumped his belongings beside him on the floor.

"Rin, I'm not going to ask how you managed to sleep in, since you we're awake when I left" Yukio muttered in between breaths, talking only loud enough so that Rin was able to hear it.

Pouting like a child he folded his arms on the desk and lowered his head, head facing towards the blonde as he brother began lecturing the class about so form of nymphs that stole socks or some crap, Rin wasn't really listen if you couldn't tell.

The other teens listened intently to the taller Okumura's teachings until the lesson stopped as an abrupt snore disrupted the class.

Without a word, Yukio grabbed the heaviest book on his desk and made his way towards Rin. His eyes were dark and very, very angry.

With an almighty swing he connected the book to Rins head, it wasn't as hard as he would have liked it but it would at least wake him up. "I will not have you disrupt my class again, Rin!" He bellowed after the book hit his brother.

With a cat like yelp Rin bolted upright in his seat, eyes wide and hands clutching at his head in pain. With a whimper he glared at his brother, fangs showing ever so slightly.

But Rin's glare was turned to the other side of the room as he heard the snickers of one of the taller males, Ryugi. "Don't laugh at me asshole!" Rin roared pointing a finger at the older male.

"And why not?" He questioned with another snicker, "That was funny as hell, teaches you to listen as well Okumura"

"Why I oughta-"

"Settle down! I will not have this classroom destroyed by you two!" Yukio glared at the two of them, with looks that could scare the hardiest of men. "No more distractions, alright?!" The rest of the class had slunk back in their seats, too afraid to interject with the situation.

Ryugi fell silent without another word, eyes trained forward, Rin on the other hand stood, breathing heavy and glaring at his brother, hands fisted by his sides, before finally taking a seat back in his chair.

Rin had bitten down hard on his lower lip to keep himself from saying something to his brother that he would regret later that night when the twins were alone in the dorm room. Rin did value his life somewhat.

"Right now that that's been settled, let's move on" Yukio addressed calmly to the class

For the duration of the lesson, not a single mutter was made by any if the students, including Rin. None if them wanted to feel the wrath of their usually composed teacher.

It wasn't until class was dismissed that the noise picked up, Yukio had collected his things and was ready to leave. "Rin, I have a mission to go to, will you be alright at the dorm alone?"

"Will you be alright in the dorm alone," Rin muttered in a dumb downed voice as he stood collecting his belongings, mocking his brother softly as he walked towards the desk, "Of course I'll be fine, you seem to forget I'm the big bro here," Rin commented with a rather large grin.

"I'm serious Rin, I don't need any more stress from you" And with a huff, Yukio stormed down the hall, away to his mission.

"Yeah yeah" Rin said waving off the others warning.

"_Riiiiiiin_" A small voice sounded, from inside the class room. It was Kuro, he had snuck out of Rins room and hidden himself under the desk and had gotten himself stuck. "_I wanted to surprise you_" The sad voice sounded.

Looking around for the small voice before catching sight of the two tailed feline, "Tsk, Kuro what are you doing bud?" He said crouching down to help the small demon free, "There you go, just remember to be more careful Kuro. I'm the dare devil here" Rin commented with a large toothy grin.

Setting the small cat free he stood to his full height, "Alright let's go"


	3. Chapter 3

**_So so sorry for not updating in ages, just been very busy with exams at school since this is my final year. But i'll be updating hopefully more frequently now. so here a small chapter to keep everyone satisfied for now :)_**

* * *

"N-no, Ushio stay with daddy" Rin cried as tears and unfortunately a trail of snot ran down his face as he cried into his worn and slightly torn manga, which was hiding behind a demon textbook his brother had assigned the class as homework. Wiping his nose and eyes on his jacket sleeve Rin momentarily looked up from his book to look at the small demon cat sitting on the desk giving Rin quite the quizzical look.

"_Why are you crying Rin?" _Kuro suddenly asked causing the teen to jump and slam the books closed.

"N-nothing Kuro just, uhm... this history section! Yeah! Really sad stuff" He lied tapping the book with his knuckles and sniffling. Rin had forgotten Yukio had assigned homework duty to Kuro before leaving, trusting the sidth to make Rin actually do his work for once.

Kuro simply stared at the boy before settling back into his previously position on the desk, curling up in the small patch of light that was slowly fading as the sun set behind the distant mountains. Watching the cat with a watchful eye Rin once again picked up his book and its current disguise and continued reading, eyes welling up once more as he read, but made sure this time to keep silent as his eyes every so often slid over to see the dozing cat.

Chuckling under his breath he whispered, "May be a demon, but sleeps as much as a normal cat."

As another hour passed Kuro had remained asleep and Rin had finished his current manga volume. Placing both the book and its disguise down Rin slid off the bed and into a standing position, stretching his back with a small mewl.

Running his tongue over his chapped lips and headed to his desk to retrieve the bottle of water he had refilled just after returning to the room. Taking a sip the demon sighed at the refreshing feeling before jumping in fright as a sudden loud knock echoed off the wooden door of the dorm room. His brows furrowed Rin placed the uncapped bottle on the desk and grabbed his clothed sword before walking over to the door when the knocking continued rapidly.

Grasping the handle Rin slowly turned the knob and opened the door.

"Mephisto?"


	4. Chapter 4

Standing before the teen stood the indigo haired demon, a smirk playing along his pale lips as his pointed fangs were shown as he began to talk, "Ah Rin I thought I would pop along for a chat." He stated simply while he absently examined his nails.

"Yeah right clown face, not today" Definitely not with just the two of them alone, Gods know what Rin would say or even do. Going to close the door unceremoniously in the others face the door was stopped by a single curled boot.

"I don't think so Okumura," He purred before kicking the door back open, "I was only here to discuss a possible raise in your allowance but I guess you don't want that" Mephisto said holding his umbrella over his shoulder, "I'll be going then," He continued before turning and making his way back down the hallway.

Eyes wide in comical surprise Rin held the door open before sprinting out of the door and began to run after the other before he was caught up, "Hey there! Maybe I was a little hasty back there," Rin said with an uneasy chuckle as he scratched the back of his head, "So what were you saying about the allowance?"

Throwing back his head the demon laugh before roughly ruffling the shorter demons hair, "I know you so well Okumura, but yes I was discussing it with the board and perhaps I was a tad harsh on your two young ones, come," He spoke before gesturing with his head to go forward, "Let's walk."

Not fazed by the others gesture Rin followed the other as Mephisto began to ramble on about possibilities in raining their allowance but only if they made sure certain chores were completed in the dorm house and blah, blah, blah. Rin began to tune out to the others babbling and began to day dream about what to cook for Yukio, Kuro and himself for dinner, or what Yukio would do if he found out that the older twin did in fact not do his homework.

Rin was brought back to reality by the soft sound of footsteps that did not belong to his bare feet or Mephisto rather chunky heeled boots. Stopping the dark haired boy opened his mouth to speak before a sudden _zwip_ and a quick sharp stab penetrated the flesh of his neck. Eyes wide he looked up at Mephisto only to seem a smirking demon, though there was a hint of something hidden within those glowing green eyes.

Turning towards the source of the shot Rin only saw a glimpse of blonde hair before the demons legs gave out from underneath him, an almighty thump echoing off the walls as his body hit the ground, eyes staring upwards as black began to cloud his vision, enclosing around his consciousness as an unknown drug coursed through his veins.

"Well done Sir Pheles," A familiar but muffled voice spoke before being responded too by a voice that was obviously Mephisto's.

"No problem indeed, though I didn't think the boy would be that easy to corner," He spoke with a small laugh.

Rin was desperate to open his mouth and speak, to scream at the two men to tell him what was going on, why the hell he couldn't move and what they were planning on doing with him, but all that escaped with a small gurgled whimper as pulsating blackness finally enclosed completely over the boy, driving him into a forceful unconscious.

_Fuck…_

**/*_*\**

_Monday Morning._

"Moriyama?"Shura called out absently was she looked down at the piece of paper listed with all the students names, freshly printed for the new week of cram class.

"Present Ms Kirigakure" The blonde chirped softly, hands idly playing with the small leaves on her familiars head.

"Okumura?" There was no response. Looking up from her papers Shura raised a brow, "Where the hell is Okumura?" She questioned scanning the room for any signs of the demon.

"He didn't show up to any of his classes today Miss" Shima called out from his mid conversation with Ryugi and Konekomaru.

"He's probably still sleeping, lazy asshole" Bon commented snidely.

Sighing heavily Shura pulled out her mobile phone and dialled Rin's number which she had saved in case of emergencies. Letting the dial ring out for a few moments she frowned and redialled the number, the same response was received.

"I'll be a moment class, just start your work," She ordered flippantly, before turning, phone in hand and exiting the room to stand in the hallway.

Looking back down at her phone she dialled Yukio's number before placing the device up to her ear, waiting on a few seconds before receiving an answer.

_"Hello?"_The slightly muffled voice answered, signal poor of the latter's behalf.

"Hey scaredy, got a problem,"

_"What is it?"_

"Well your precious big bro hasn't showed up to class"

With a heavy sigh the voice responded, _"He's probably skipping or still asleep Shura, you know him."_

"I know, still, want me to check it out?"

Another sigh could be head from the other, _"Yeah, if you can."_

Nodding to herself the red head muttered a 'gotcha' before hanging up and poking her head back into the classroom, "Be back in a minute kids, gotta go look for Okumura."

A groan in unison was heard from Ryugi and Izumo, "Just leave the idiot! Not like he'll pay attention anyway," Ryugi commented before being nudged by an irritated Renzo. Ignoring the others words Shura exited the room and made herself to one of the closest doors and slid in her key turning the lock and exiting through to enter the school campus no too far from the dormitory rooms where Yukio and Rin resided.

Walking up the seemingly endless stairs Shura finally reached the door. Wrapping her hand around the handle she was surprised to find it unlocked, "That's strange, even for Rin," She commented softly to herself before silently opening the dorm door and entering the building and scaling the empty hallways for any sign of the raven haired boy. Though the building was large it was unnervingly quiet as the busty redhead inaudibly made her way upwards and towards the room the twins shared. Reaching the hallway leading to the room Shura had noticed one of the doors was left wide open.

One hand placed over her chest she muttered, "Devour the eight princesses, slay the serpent," as a dim light illuminated her chest and her weapon slide from her flesh. Gripping the blade tightly she made her way to the entry way of the door and peeked in. The room seemed uninhabited, the bed on the left was messy and had a small pile of manga and unopened textbooks residing on it, obviously Rin's bed. Entering the room slowly, Shura studied her surroundings. Looking at the desk she had noticed the opened but not empty water bottle sitting there idly, going stagnant in the light.

Sniffing the air there seemed no scent of 'boy' sitting anywhere in the air which made Shura's stomach not in nervousness. Looking around a sudden mewl from down the hall caught the females attention. Running out she say a small and rather distressed Kuro galloping down the hallway, meowing loudly and in a tone that suggested he was scared.

_"Rin! Rin where are you!?"_ The demon called thought Shura could not understand a word he said. Spotting the female Kuro made a b-line directly for the exorcist and dived up into her arms, his eyes large and watery as he mewled pathetically.

"What is it boy?" Shura questioned, frustrated that she could not understand the others familiar.

The cat sidth continued to mewl and whimper, squirming in the others grasp, _"He's gone he's gone he's gone!"_He mewled in worry.

Sighing she placed the animal down and looked around the hall before something caught her eye coming from the bedroom. Peering back inside on floor sat the red casing Rin had used to cover his sword.

"He never takes his sword without…" She spoke to herself softly as she thought for a moment before breaking out into a sprint down the hall and out of the building, "Shit." Running the red head had flipped open her phone and dialled the only number she had on speed dial, "Okumura? We have a problem."


	5. Chapter 5

Groggy and disorientated Rin's eyes fluttered beneath the lids for a few moments before finally opening slowly, sight blurred by sleep but slowly focussing as he realised he was no longer in his room, or even the dormitory building. Going to sit up the dark haired teen noticed that his hands were bound to the metal frame of a flimsy bed he had been place on. Craning his neck to look Rin also noticed his feet were bound to the same frame.

Eyes widened with confusion and fear Rin's tail began to sway in panic, the movement causing the boy to noticed something was attached to the black appendage. Arching his hips he allowed his tail freedom from beneath his form and to lay beside him on the bed, the base of the tail had a small metal cuff like object with engrave symbols on them which seemed to glow slightly in the artificial light of the room.

"Where am I…? How long was I out?" He questioned himself softly, his voice rough and gravelly from lack of moisture. Coughing the demon continued to try and free himself, but to no avail as his bindings would not budge. "What the hell…?"

"Finally awake I see," A sudden deep chuckle brought Rin from his wondering to look up once more at the source of the sound. There stood Mephisto clad in his normal attire, though his pantaloons were replaced with a pair of average white slacks. Beside him stood a black clad exorcist, blonde hair spiked neatly as a pair of thin framed black glasses framed his dark eyes.

"What's going on clown!" Rin yelled fiercely whilst struggling against his binds but with no success.

Smirking the purple haired king began to speak, "Well Okumura, the Vatican has decided whether or not you pass your exorcist exam that you are not fit to be around humans, teenage student to be exact. So instead of having you as a possible danger to Assiah, they have decided to use you as a weapon" He said casually as if this information would not stun the dark haired boy.

"A weapon! I won't, you can't make me"

"Oh Rin, I'm afraid you don't have a choice in the matter, you see, for the 200 years I've been partakingin the Vatican, of my own free will of course, I've had my powers severed in two via... this contraption" The indigo haired demon said holding up a small metal cuff, similar to the one of Rin's wrists and tail, "It's made of the same metal binding your body and tail down. A few simple words and phew boy does it hurt. So Rin, if you thought I was powerful with this binding, you have no idea what you're in for."

Swallowing thickly Rin was unsure what exactly what was going to happen to him. The Vatican wasn't really going to make him a weapon were they? Were they going to make him kill people?

"So sit back, relax and... enjoy." The taller male spoke before making his way over to the struggling demon, standing over his body like a looming beast.

"E-Enjoy what?" The raven haired boy asked, cursing himself internally for that damn stutter.

With a chuckle resonating deep in his throat, he closed his eyes for a moment before opening them wide, swirls of blues of purples swam through the green abyss of the demons eyes as they drew the younger demon into his taunting grasp. "Now Rin" He purred, voice almost as demonic as his eyes, "You _are_going to obey me," He continued slowly in a gravelly tone before closing his eyes once more and cutting off the connection he had seemed to create and wincing as the metal cuff was reattached to his tail by the exorcist accompanying him. "But just to be safe," Mephisto added as he stood to his full height and looking over at the other exorcist with a slight glare, and a nod "Do it." He ordered.

Nodding, the unnamed exorcist took his place beside the taller demon, in his hands help a syringe filled with a strangely coloured fluid.

"This may pinch a little, but I assure you Rin, you'll see from our side soon enough," And with that Mephisto turned on his heel and headed towards the door, heels of his boots clicking on the harsh flooring as he left.

"Mephisto! Tell me what's going on! Mephisto!" The elder Okumura screamed out as his arm was braced even more so against the bed as the cool metal tip of the needle was inserted into his flesh, "Mephisto!" Everything began to swirl together and then…

Black.


	6. Chapter 6

The snarling creatures continued to hurl themselves in the direction of Yukio and the small squad that was quickly making short work of the ghouls that inhabited the deceased corpses of animals that once inhabited the expanse of forest they were currently camping in.

"Nanase on your left!" The leader, which was conveniently Yukio, cried out as he continually shot of the rotting forms.

"Mitori your right!" Another voice within the squadron called out as a short female exorcist with chestnut hair ordered her familiars which were a pair of six foot greenmen whose limbs were extending and manipulating to provide protection to the squad as well as injure the oncoming wave of ghouls.

As the group of four continued to fight, all were unaware to a small squirrel that had been inhabited by a demon leap from a nearby tree and sink its teeth into Mitori's shoulder. With a cry of pain she slapped the beast away and it was quickly killed by the branch of her familiar. "Mitori!" A male voice called before lowering his sword and rushing to her side, it was Shino Tujiyuka, her partner in both senses.

"Are you alright?" He questioned worried as the rotting steam rose form the flesh on her shoulder.

Nodding weakly her familiar's turned and created a barrier around the two, their branches entwining and forming a large circular mass of leaves and branches leaving only the light through the small gaps in the wood.

"I'll have to tend to your wound here Haruka,"

"I'll be fi—"

"No." Tujiyuka complied firmly whilst adjusting her shirt to reveal the wound. Calling out to Mitori's familiars the knight slash doctor pleaded for the medical herbs needed to treat the wound. With a low murmuring grumble the branches moved once again, extended branches moving downwards towards the couple as specific medicinal herbs and leaves sprouted immediately from the bark.

Outside the barricade Nanase and Okumra continued to fight until the last ghoul had dropped dead on the ground before disintegrating into dust. Panting heavily Yukio wiped a hand across his brow and looked over to his partner to see if he was ok. Both nodding at one another, Yukio accessed the barricade through a newly formed opening caused by one of the greenmen as Nanase performed a purification chant to cleanse the forest of any other lurking ghouls.

As the blonde began to engrave in the dirt and mutter under his breath, Yukio put away his guns as he entered to see the couple on the ground, Mitori panting heavily as Tujiyuka knelt beside her, hands delicately tending to her wounds as steam hissed around them as the bite bubbled and trembled.

Hissing softly the female allowed her hands to clench in the coat of her lover, tears forming in the corners of her eyes as her wounds were tended too, "Ow…"

"I know I'm sorry…" The brunette mumbled apologetically as he chewed on his lower lip.

Seeing there was nothing Yukio could do at the moment seeing the other had all his medical needs catered for. Frowning, Yukio turned and left the barricade to check on the ritual as his phone began to ring and vibrate in his pocket. Pulling the device out, he read the name flashing on the screen before answering.

"Okumura speaking," On the other said a panicked female voice spoke with words that caused the younger twins knees to shake and almost give out beneath him, the muscles in his hand not that strong and causing the phone to slip from his fingers and rattle to the ground as the voice continued to speak loudly.

_"Yukio? Yukio!"_

"Rin…"


End file.
